Biodiversity Data Journal 5: e20997 doi: 10.3897/BDJ.5.e20997 Monograph Polychaetes of Greece: an updated and annotated checklist Sarah Faulwetter‡, Nomiki Simboura§, Nikolaos Katsiaras§,|, Giorgos Chatzigeorgiou¶, Christos Arvanitidis¶ ‡ University of Patras, Department of Zoology, Section of Marine Biology, Patras, Greece § Institute of Oceanography, Hellenic Centre for Marine Research, Anavyssos, Greece | Department of Marine Sciences, University of the Aegean, Mytilini, Greece ¶ Institute of Marine Biology, Biotechnology and Aquaculture, Hellenic Centre for Marine Research, Heraklion Crete, Greece Corresponding author: Sarah Faulwetter ([email protected]) Academic editor: Vasilis Gerovasileiou Received: 14 Sep 2017 | Accepted: 13 Dec 2017 | Published: 22 Dec 2017 Citation: Faulwetter S, Simboura N, Katsiaras N, Chatzigeorgiou G, Arvanitidis C (2017) Polychaetes of Greece: an updated and annotated checklist. Biodiversity Data Journal 5: e20997. https://doi.org/10.3897/BDJ.5.e20997 Abstract Background The last annotated checklist of marine polychaetes in Greece was published in 2001. Since then, global taxonomic progress, combined with many new species records for Greece, required a thorough review of the taxonomic, nomenclatural and biogeographic status of the national species list. This checklist revises the status of all extant polychaete species reported from the Greek Exclusive Economic Zone since 1832. The work was undertaken as part of the efforts on compiling a national species inventory (Greek Taxon Information System initiative) in the framework of the LifeWatchGreece Research Infrastructure. New information This checklist comprises an updated and annotated inventory of polychaete species in Greek waters, compiled from literature reports, online databases, museum collections and unpublished datasets. The list provides information on 836 species-level taxa from Greece, of which 142 are considered questionable. An additional 84 species reported in the past © Faulwetter S et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 2 Faulwetter S et al are currently considered absent from Greece; reasons for the exclusion of each species are given. Fourteen species are reported here for the first time from Greek waters. At least 52 species in the present list constitute in fact a complex of cryptic or pseudo-cryptic species. Forty-seven species are considered non-native to the area. In addition to the species-level taxa reported in this checklist, eleven genera have been recorded from Greece with no representatives identified to species level. One replacement name is introduced. For each species, a comprehensive bibliographic list of occurrence records in Greece and the synonyms used in these publications are provided as supplementary material. Where necessary, the taxonomic, nomenclatural or biogeographic status is discussed. Finally, the findings are discussed in the wider context of Mediterranean polychaete biogeography, taxonomic practice and worldwide research progress. Keywords Eastern Mediterranean, Polychaeta, Annelida, inventory, biodiversity, new records, replacement name Introduction Polychaete research in Greece The history of polychaete studies in Greece can be traced back to classical antiquity. Aristotle, although he tended to neglect polychaetes in his works on natural history (Voultsiadou et al. 2017) gave the first description of a “scolopendra thalassia” (referring to Hermodice carunculata Pallas, 1776): “There are also marine scolopendras, similar to the terrestrial ones, but smaller in size; they live on the rocky substrates. Their colour is richer red and they bear more and much slender feet than the terrestrial scolopendras. They do not occur in great depths, as do the marine snakes” (History of Animals, 4th century B.C.). Modern systematic polychaete research in the country started in the 19th century (e.g. Brullé 1832, Forbes 1842, von Marenzeller 1893). Since then, most research has been directed towards the study of macrobenthic coastal soft bottom polychaete communities in an ecological context. To date, the only taxonomic work studying exclusively planktonic polychaetes in Greece is by Wesenberg-Lund (1939a), based on samples taken during the Danish Oceanographic Expedition of the research vessel “Thor” from a few stations in Greek waters (Mavraki et al. 2016). Hard substrates, meiobenthic communities and deep sea habitats are understudied in Greece (e.g. Tselepides et al. 2004) while no terrestrial or fresh water polychaetes are known from the country. Specialised taxonomic or faunistic works from Greece are rare and the large body of ecological studies comprises the most important source for species records and thus for the creation of national checklists. Polychaetes of Greece: an updated and annotated checklist 3 Rationale for the checklist The first polychaete checklists covering the Greek waters were those of Arvanitidis (2000a) for the Aegean Sea (including the Turkish Aegean and the Sea of Marmara) under the broader framework of the entire Mediterranean inventory and of Simboura and Nicolaidou (2001) for all Greek seas; both checklists included only benthic species. In the framework of the European Union project PESI (Pan-European Species directories Infrastructures), Faulwetter (2010) combined the above lists and additional sources into an updated checklist, but this was simply a computer-based compilation of existing sources without further verification or annotation of the records. After 2001, marine research, including benthic surveys (carried out by the Hellenic Centre for Marine Research (HCMR) and several universities) was intensified. Many new species records – often not only new for Greece, but also for the Mediterranean Sea – resulting from these studies, as well as the worldwide progress of taxonomic knowledge, required a thorough review of the taxonomic, nomenclatural and biogeographic status of many polychaete species recorded from Greece. The construction of the Greek Taxonomic Information System (Bailly et al. 2016), which forms the taxonomic backbone of the LifeWatchGreece Research Infrastructure, provided the framework for the present study: the compilation of a comprehensive, annotated and updated checklist of the Greek polychaete fauna, expanding and updating former works (i.e. Arvanitidis 2000a, Simboura and Nicolaidou 2001). In addition, this publication complements recent checklists from other areas of the Mediterranean and Black Sea (e.g. Çınar 2005, Castelli et al. 2008, Ayari et al. 2009, Zaâbi et al. 2009, Martín and Gil 2010, Zaâbi et al. 2012, Çınar et al. 2014, Mikac 2015) and thus serves as an information resource for future polychaete studies in this biogeographic region. Taxonomic scope Several recent studies indicate the paraphyletic status of polychaetes (e.g. Rouse and Pleijel 2001, de Oliveira Almeida et al. 2003, Weigert and Bleidorn 2016) and the higher classification of Annelida has been in a constant flux over the last years (e.g. Zrzavý et al. 2001, Helm et al. 2012, Weigert and Bleidorn 2016). As the phylogenetic position of many groups within the Annelida is not yet resolved, we chose to restrict the "polychaetes" to their traditional definition in this checklist and include those clades covered by Rouse and Pleijel (2001). We anticipate this approach to be more helpful to the majority of users of this checklist than following the most recent phylogeny which would exclude certain "traditional" polychaete families (see Weigert and Bleidorn 2016). Geographic scope and characteristics of the region This checklist includes all polychaete taxa reported from the waters of the Greek Exclusive Economic Zone (EEZ) (as delimited by the Marine Regions database, see also Bailly et al. 2016). It does not cover a biogeographic area but constitutes an inventory of the national 4 Faulwetter S et al polychaete fauna. Thus, species reported from neighbouring countries but not (yet) from Greece are not included in this list, despite the fact that they are highly likely to occur in Greek water too. Greece is located centrally in the Eastern Mediterranean Sea and thus lies in one of the world's marine biodiversity hotspots (Bianchi and Morri 2000a, Coll et al. 2010). Its coastline stretches over 18,000 km, showing a variety of coastal landforms, from cliffs and rocky shores to beaches, lagoons and river deltas and encompassing around 9,800 islands and rocky islets (Issaris and Salomidi 2012). The Greek EEZ comprises parts of three biogeographically distinct water bodies: the Aegean Sea in the east, the Ionian Sea in the west and the Libyan Sea in the south. The Aegean Sea exchanges waters in the north with the Black Sea through the Bosphorus Strait, the Marmara Sea and the Strait of Dardanelles. Extensive faulting and vertical tectonic movements have resulted in the fracturing of the Hellenic mountain chains and the creation of deeply incised embayments and semi-enclosed basins, whereas active underwater volcanoes and shallow-water hydrothermal vents can be found in several places in the Aegean Sea (Dando et al. 1999; see also Sini et al. (2017) for a detailed overview of the ecology of the Aegean Sea). The island of Crete forms the southern border of the Aegean and separates it from the Libyan Sea. The Libyan Sea is characterised by deep sea features such as trenches,